1. Field of the Invention
The present invention regards separation of liquid from gas. In particular, the present invention regards a scrubber with beneficial properties.
2. Description of the Related Art
A number of known installations function to separate fluids of different density by use of a cyclone principle. The principle works by the deflection of a compounded fluid flow for example along the inner wall of a vessel, whereby the heavier constituents move to the outside of the curved fluid flow and are accumulated towards the inner wall of the vessel, after which the heavier constituents as a result of gravitation can be directed to a reservoir or outlet in the bottom of the vessel. The lighter constituents will be concentrated in the center area of the vessel, after which they can be taken out through an outlet beginning in the center area of the vessel.
Some examples of cyclones that can be used for separation of fluids of different density can be found in patent publications NO 308199 and NO 144128, which regard hydrocyclones. The publications teach separation of fluids in the form of liquids, or even liquids with contents of solid constituents, which are fluids of relatively high viscosity. For fluids of high viscosity it is essential to avoid unnecessary pressure loss, which problem is described in the publications.
Pressure loss is also an essential problem with respect to separation of liquids and/or particles from a fluid flow that in substance comprises gas. This is described in patent publication NO 176309, which discloses a device for separation of liquid and/or particles from a high pressure gas flow. In this publication, on page 1, lines 32-38, it is set forth: “The gas density is a very important parameter with respect to the efficiency of a centrifugal gas separator. In general the collection efficiency and also the pressure loss of a centrifugal separator achieve the most preferable values when the flow through the separator is an ideally arranged centrifugal flow on which no other flow such as turbulence and secondary flows have influence.”
The device according to NO 176309 comprises a cylindrical vessel with an in substance vertical axis, equipped with: an upper compartment to which gas is fed; an intermediate compartment comprising a number of vanes that are arranged in spiral around the axis; a lower compartment for separation of gas and liquid and/or particles and a coaxial gas outlet pipe extending upwards from the lower compartment through the intermediate compartment and upper compartment, around which spiral formed vanes have been provided; which device is distinguished in that each spiral formed vane is comprising a lower part with a constant slope and a part with a slope that increases gradually in upward direction.
The vanes of the above mentioned device bring the gas into rotation, and the vanes are arranged on the coaxially arranged gas outlet pipe.
In patent publication GB 1119699 an inlet is described that is directed downwards, in contrast to the conventional vane inlet (Schepentoeter) that is directed outwards. The inlets are significant for how the flow is distributed into the scrubber.
Despite devices as those mentioned above, a demand still exists for improvements, in particular with respect to a device that in agreement with the above has most beneficial properties when the flow through the separator is an ideally arranged centrifugal flow on which no other flow such as turbulence and secondary flows have influence. The objective of the present invention is to provide a device that is contributing to meet the above mentioned demand.